[RFC v2 08/10] pseries/papr-hvpipe: Simplify error handling in papr_hvpipe_init()

["Ritesh Harjani (IBM)" <ritesh.list@gmail.com>]

Remove such 3 levels of nesting patterns to check success return values
from function calls.

ret = enable_hvpipe_IRQ()
    if (!ret)
	    ret = set_hvpipe_sys_param(1)
	        if (!ret)
		    ret = misc_register()

Instead just bail out to "out*:" labels, in case of any error. This
simplifies the init flow.

Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
---
 arch/powerpc/platforms/pseries/papr-hvpipe.c | 26 +++++++++++---------
 1 file changed, 15 insertions(+), 11 deletions(-)

diff --git a/arch/powerpc/platforms/pseries/papr-hvpipe.c b/arch/powerpc/platforms/pseries/papr-hvpipe.c
index ac2c4b42b373..5d04d1fa4370 100644
--- a/arch/powerpc/platforms/pseries/papr-hvpipe.c
+++ b/arch/powerpc/platforms/pseries/papr-hvpipe.c
@@ -783,23 +783,27 @@ static int __init papr_hvpipe_init(void)
 	}
 
 	ret = enable_hvpipe_IRQ();
-	if (!ret) {
-		ret = set_hvpipe_sys_param(1);
-		if (!ret)
-			ret = misc_register(&papr_hvpipe_dev);
-	}
+	if (ret)
+		goto out_wq;
 
-	if (!ret) {
-		pr_info("hvpipe feature is enabled\n");
-		hvpipe_feature = true;
-		return 0;
-	}
+	ret = set_hvpipe_sys_param(1);
+	if (ret)
+		goto out_wq;
 
-	pr_err("hvpipe feature is not enabled %d\n", ret);
+	ret = misc_register(&papr_hvpipe_dev);
+	if (ret)
+		goto out_wq;
+
+	pr_info("hvpipe feature is enabled\n");
+	hvpipe_feature = true;
+	return 0;
+
+out_wq:
 	destroy_workqueue(papr_hvpipe_wq);
 out:
 	kfree(papr_hvpipe_work);
 	papr_hvpipe_work = NULL;
+	pr_err("hvpipe feature is not enabled %d\n", ret);
 	return ret;
 }
 machine_device_initcall(pseries, papr_hvpipe_init);
-- 
2.39.5